Abstract
In the previous article (Kosaki, Shi, Matsui, Shimbo, & Fujimaki, 2015) we reviewed studies regarding how animals represent temporal information in classical conditioning. In this article, we first review various issues pertaining to interval timing in operant conditioning, with the main goal of providing a concise summary of procedural and theoretical developments in interval timing research. In the remainder of the article, we will review recent empirical findings and theories about the neural substrates underlying timing mechanisms both in classical and operant conditioning, and discuss how the hippocampus and striatum might contribute to different aspects of temporal information processing during conditioning. We then argue that the potentially different timing mechanisms implemented by the hippocampus and the striatum, as evidenced by the recent discovery of time cells in the hippocampus and consistent findings regarding involvement of the striatum in interval timing, might each be considered to constitute a part of functionally dissociable multiple memory systems that have been described elsewhere in the literature, particularly in the context of spatial learning and the organisation of voluntary behaviour.
